CIRCULATION PUMP FOR COOLING MECHANICAL FACE SEAL OF SUBMERSIBLE WELL PUMP ASSEMBLY

A modal attenuator includes annular chambers disposed between an attenuator body and a perforated screen surrounding a primary flow path. The modal attenuator in some arrangements is in the form of an expander section. In some arrangements one or both of the height and the width of the annular chambers may vary along the length of the attenuator body such that the volumes of the chambers vary along the length of the attenuator body. Each chamber preferably has an open end facing the perforated screen such that acoustic waves passing through the perforated screen can enter into the chamber through the open end. An electrical submersible pump assembly includes a production pump, a motor containing a motor lubricant, and a seal section coupled between the motor and the pump. A drive shaft extends through the seal section, the drive shaft being rotated by the motor for driving the production pump. A mechanical face seal in the seal section seals around the shaft. A circulation pump is mounted to the shaft above the face seal for rotation therewith. An inlet passage leads from an exterior of the seal section to the circulation pump to deliver well fluid to the circulation pump. An outlet passage leads from the circulation pump to the exterior of the seal section to discharge well fluid exterior of the seal section. The rotating component of the face seal is located in the outlet passage.